Crack from cleric and fool in church (8)
I believe the answer is:
crevasse
'crack' is the definition.
(crevasse is a kind of crack)
'cleric and fool in church' is the wordplay.
'cleric' becomes 'Rev' (abbreviation for Reverend).
'and' means one lot of letters go next to another.
'fool' becomes 'ass' (both can mean a stupid person).
'in' indicates putting letters inside.
'church' becomes 'ce' (abbreviation for Church of England).
'rev'+'ass'='revass'
'revass' put within 'ce' is 'CREVASSE'.
'from' is the link.
(Other definitions for crevasse that I've seen before include "cold break" , "climbing hazard in glacier" , "Crack in a mountain slope or a glacier" , "Sever sac (anag)" , "Deep glacial crack" .)